Romney son apologizes for ‘dumb joke’

CONCORD, N.H. -- Mitt Romney's son cracked a joke about President Barack Obama's birth certificate at a New Hampshire event Friday, following it up with an apology on Twitter.

Asked whether the Republican presidential candidate would release his tax returns, Matt Romney said, "I heard someone suggest the other day that as soon as President Obama releases his grades and birth certificate and sort of a long list of things, then maybe he'd do it," according to a video on the local news website Patch.com.

"That was not my dad saying that," jumped in another son, Tagg Romney.

Matt Romney followed up his remarks with an apology via Twitter. "I repeated a dumb joke. My bad," he tweeted.

The candidate will attend campaign events in New Hampshire on Friday evening and Saturday morning before returning to Iowa for a 10-stop swing through the state.

The joke was a reminder of the difficulty of deploying campaign surrogates while controlling Romney's tightly scripted message. Romney's sons have been more scarce on the trail than during his previous presidential campaign in 2008 and have generally kept quiet on Twitter.